Fluid hydroforming process



ug. 28, 1,9756 I R. J. FRITZ ET AL 2,760,911

FLUID HYDROFORMING PROCESS Filed Dec. 26, 1951 Qolaafvf. Trulia John i4.moesen?, Jr'.

afar (Jdbolsorz {Slm/embers Jlief CZ. Qex

United States Patent FLUID HYDROFORMING PROCESS Robert J. Fritz, John F.Moser, Jr., Lloyd A. Nicolai. and Edward W. S. Nicholson, Baton Rouge,La., and Walter A. Rex, Westfield, N. J., assignors to Esso Research andEngineering Company, a corporation of Delaware Application December 26,1951, Serial No. 263,445

8 Claims. (Cl. 19d-50) This invention relates to the catalyticconversion of hydrocarbon fractions boiling within the motor fuelboiling range of low knock rating into high octane number motor fuelsrich in aromatics and lparticularly to a process whereby such aconversion is effected by the uidized solids technique.

Hydroforming is a well known and widely used process for treatinghydrocarbon fractions boiling within the motor fuel or naphtha range toupgrade the same or increase the aromaticity and improve the anti-knockcharacteristics of said hydrocarbon fractions. By hydroforming isordinarily meant an operation conducted at elevated temperatures andpressures in the presence of solid catalyst particles and hydrogenwhereby the hydrocarbon fraction is increased in aromaticity and inwhich operation there is no net consumption of hydrogen. Hydroformingoperations are ordinarily carried out in the presence of hydrogen or ahydrogen-rich recycle gas at temperatures of 750-l150l F. in thepressure range of about 50-1000 lbs. per sq. inch and in con'- tact withsuch catalysts as molybdenum oxide, chromium oxide or, in general,oxides or ysuliides of metals of v Groups IV, V, VI, VII, and VIII ofthe Periodic Systern of elements, alone, or generally supported on abase or spacing agent such as alumina gel, precipitated alumina or zincaluminate spinel. A good hydroforming catalyst is one containing about10 wt. per cent molybdenum oxide supported on alumina or upon zincaluminate spinel.

It has been proposed in application Serial No. 188,236,

filed October 3, 1950, now Patent No. 2,689,823 to effect thehydroforming of naphtha fractions in a fluidized solids reactor systemin which naphtha vapors are passed continuously through a denselluidized bed of hydroforming catalyst particles in a reaction zone,spent catalyst particles are withdrawn from the dense bed in thereaction zone and passed to a separate regeneration zone whereinactivating carbonaceous deposits are removed by combustion whereuponthe regenerated catalyst particles are returned to the main reactorvessel or hydroforming reaction zone. Fluid hydroforming as thusconducted has several fundamental advantages over fixed bed hydroformingsuch as (l) the operations are continuous, (2) the vessels and equipmentcan be designed for single rather than dual function, (3) the reactortemperature is substantially constant throughout the iiuidized catalystbed, and (4) the regenerationor reconditioning of the catalyst may bereadily controlled;

A particular advantage of the foregoing fluid solids operation has beenthe fact that the freshly regenerated catalyst can be utilized to carrypart of the heat required for the hydroforrning reaction from theregeneration zone into the reaction zone. It has been proposed in thisconnection to discharge hot, regenerated catalyst particles from theregenerator standpipe into a stream of hot, hydrogen-rich recycle gas in-a transfer line whereby the catalyst particles are subjected to areconditioning treatment involving at least a partial reduc- 2,760,9 llPatented Aug. 28, 1956 tion of higher oxides of the catalytic metalformed during regeneration to a lower or more catalytically active fermof catalytic metal oxide during its passage through the transfer lineinto the reaction Zone. In view of the high temperature of theregenerated catalyst (1059"- 1300 F.) and the exothermic character ofthe reaction between the hot, freshly regenerated catalyst and thehydrogen it is necessary to make the transfer line very short and ofsmall diameter in order to keep the time of Contact of the catalyst andhydrogen-containing gas sufficiently short to avoid overtreatment and/orthermal degradation of the catalyst.

lt is the object of this invention to provide a novel method fortreating freshly regenerated hydroforming catalyst preparatory torecycling the same to a iluidized solids hydroforming reaction zone.

It is a further object lof this invention to provide a novel method oftreating the freshly regenerated hydroforming catalyst at lowtemperatures for relatively long periods of time.

It is also an object of this invention to provide a novel method fortreating freshly regenerated hydroforming catalyst at low temperaturesfor long periods of time while causing the gaseous products from thepretreatment to by-pass the main reactor bed.

These and other objects will appear more clearly from the detailedspecification and claims which follow:

It has now been found that hot, freshly regenerated hydroformingcatalyst can be most advantageously pretreated with ahydrogen-containing gas to convert higher catalytic metal oxides formedduring regeneration to a lower or more catalytically active form ofcatalytic metal oxide if the hot regenerated catalyst is intermixed witha stream of recycle reactor catalyst before or at the same time thathydrogen-rich gas is first brought into contact with the regeneratedcatalyst, and the gaseous products from the pretreatment, principallythe water formed by the reduction of the catalytic metal oxide, areby-passed around the reactor bed. In this manner contact of the freshlyregenerated catalyst with hydrogen-rich gas can be effected at lowertemperatures 'for periods as long as l5 minutes or more withoutovertreatment and/or thermal degradation of the catalyst While at thesame time heat formed in the regenerator.

is effectively transferred to the reactor side by transfer of thesensible heat of the regenerated catalyst to thev t recycle reactorcatalyst. By discharging the gaseous the reactor or into the productsoutlet line from the reactor, contact of the water vapor formed in thepretreating operation with the main reactor catalyst bed is avoidedthereby avoiding the deleterious effects of water vapor upon thecatalyst under hydroforming reaction conditions.

Reference is made to the accompanying drawing illustrating a schematicilow plan in accordance with the present invention.

In the drawing 10 is a reactor vessel provided at the bottom with aninlet line 11 for the introduction of hot, hydrogen-rich or recycle gas.A perforated plate or grid 12 is preferably arranged near the bottom ofthe vessel in order to insure uniform distribution of the incomingrecycle gas over the entire cross section of the reactor vessel. Aseparate inlet 13 is shown for the introduction of the naphtha feed to adistributor ring 55 above the grid member 12 although the feed may, if

desired, be introduced separately or in admixture withl turbulent bed 14of catalyst and vapors having a definite level L superposed by a diluteor disperse phase 15 comprising small amounts of catalyst entrained inthe vaporous reaction products. The reaction products are taken overheadfrom the reactor, preferably through a cyclone separator 16 or the likefor separating entrained catalyst particles which are returned to thedense bed 14 via a dip leg attached to the bottom of the cycloneseparator. Reaction products are taken overhead through outlet line 17and conducted to suitable fractionating, pressure release, or otherprocessing equipment and then to storage.

Catalyst particles are continuously withdrawn from the dense bed 14through withdrawal conduit 18 into an external stripper 19. It will beunderstood that the stripper could also be arranged within the reactorvessel as by providing a vertical conduit or cell, preferably extendingabove level L and provided with an orifice or port below dense bedIlevel L for controlling the discharge of catalyst directly from densebed 14 into the conduit or stripper cell. A tap 20 is provided `at thelower portion of the stripper for introducing a suitable stripping gassuch as steam, nitrogen, or the like which will serve to removeentrained or adsorbed hydrogen or hydrocarbon materials that wouldotherwise be carried to the regeneration zone and burned therein. Thestripping gas and stripped gases pass overhead from stripper 19 throughline 21 and into the upper part of the reactor vessel through line 22 inthe event that substantial amounts of catalyst are entrained in thestripping gas and recovery thereof in reactor cyclone separator 16 isdesired, or through line 23 into product outlet line 17 in the eventthat it is desired to have the stripping gas bypass the reactor. Thelower end of the stripping vessel is necked down and attached to conduit24 and forms therewith a standpipe for developing sufficient uistaticpressure to assist in the transfer of stripped spent catalyst to theregenerator vessel. A slide valve 25 or the like is provided near thebase of the standpipe 24 tocontrol the withdrawal of catalyst from thereactor vessel. If desired or necessary, one or more gas taps can beprovided along standpipe 24 to supply iluidizing gas thereto.

The stripped spent catalyst is discharged from the base of the standpipe24 into transfer line 26 where it is picked up by a stream ofregeneration ,gas or air supplied through line 27 and compressor 28 andconveyed into the bottom of regenerator vessel 30. A perforated plate orgrid member 31 is preferably arranged in the bottom of the regeneratorto insure uniform distribution of the catalyst and gases over the entirecross-section of the regenerator. In order to avoid over-treatment ofthe catalystA in transfer line 25 it is preferable to use only part ofthe air necessary .for the regeneration for conveying the spent catalystthrough the transfer line 26 and to add the remainder of the airnecessary for regeneration through a separate line 32 or additionallines discharging directly into the regenerator 30,

The superficial velocity of the regeneration gases through regenerator30 is so controlled as to form a dense iluidized, turbulent bed 33 ofcatalyst particlesand gas having a definite level L' which is superposedby a dilute or disperse phase 34 in the upper part of the regenerator 30comprising small amounts of catalyst entrained in the regenerationgases. The regeneration gases are taken overhead from regenerator 30,preferably after passage through a cyclone separator 35 or the likewhich serves to remove most of the catalyst particles from theregeneration gases. The catalyst particles are returned to the dense bed33 through the dip pipe attached to the bottom of the cyclone separator.The regeneration gases, substantially free from catalyst particles, arewithdrawn overhead through line 36 which is provided with a pressurecontrol valve and passed to a waste gas stack or to suitable washing andstorage equipment in the event that it is desired to use theregeneration gases 'for stripping purposes. In view of the fact that theoxidative reactions that occur in the regenerator generate more heatthan can normally be transferred to the reactor by the circulatingcatalyst at low catalyst to oil ratios without exceeding safetemperature limits, it is ordinarily necessary to provide cooling coilsin the regenerator. A very desirable arrangement is to provide a primarycooling coil entirely below the level L and a secondary cooling coilpartly below and partly above the dense bed level L to permit adjustmentof the heat transfer capacity by simply varying the dense bed level L inthe regenerator.

Regenerated catalyst overows from dense bed 33 into a stripping cellformed by conduit 37. The conduit 37 may, if desired be extendedupwardly above dense bed level L' and an orifice or port may be providedin the wall of the conduit below the level L' of the dense bed 33 forwithdrawal of catalyst directly from the dense bed, or the stripper maybe arranged externally of the regenerator vessel v30 with a connectorpipe for discharging catalyst from the dense bed into the stripper andwith an outlet line connected to the top of the stripper for dischargingstripping gas and stripped constituents into the dilute phase 34 in theupper part of regenerator 30 or into outlet line 36.

A stripping gas is introduced into the stripper cell at 38 and, ifdesired, further amounts of stripping gas may be introduced at 39.Suitable stripping gases are air, nitrogen yor iiue gas, or mixtures ofthese` It is preferred to introduce `air at 38 to strip and/or effect anal clean up of the regenerated catalyst and then to purge the stream ofregenerated catalyst of any residual air or carbon oxides by introducinga small amount of nitrogen at 39.. If flue gas is used for stripping theregenerated catalyst it is preferred to wash it yfree of carbon monoxideand carbon dioxide since it is advisable to exclude these gases from thereaction zone. p

The bottom of conduit 37 is connected to conduit 40 and forms therewitha standpipe for facilitating the transfer of regenerated catalyst to thereactor. A slide valve 41 or the like is arranged near the base of thestandpipe in order to control the discharge of stripped regeneratedcatalyst into transferline 42. v

A conduit 43 extends upwardly from the bottom of reactor vessel 10through distributor grid 12 into the lower portion of dense bed 14..Catalyst ows from the reactor dense bed 14 into the upper end of conduit43 and passes downwardly therethrough into conduit 44 countercurrent toa stream of recycle lgas introduced at line 45. Conduits 43 and 44 ,forma `standpipe for facilitating the circulation of a stream of recyclereactor catalyst. A slide valve 46 or the like is arranged near the baseof the standpipe for controlling thev discharge of recycle reactorcatalyst intotransfer line 42. A stream of hydrogen-rich recycle gas issupplied through line 47 to convey the recycle reactor catalyst throughtransfer line 42 4and to mix the recycle reactor catalyst with thefreshly regenerated catalyst discharged from standpipe 40 into thetransfer line 42. The mixture of regenerated catalyst and recyclereactor catalyst passes through riser 48 into a cyclone separator 49 orthe like for separating the hydrogen-containing or pretreating gas fromthe mixture of recycle reactor catalyst and freshly regeneratedcatalyst. Additional inlet lines may be provided along transfer lline 42and riser 48 for the introduction of further amounts of hydrogen-richgas to effect transfer of the catalyst particles as well as thepretreatment or partial reduction of the freshly regenerated catalyst.The riser 48 may ordinarily be designed to give adequate contact betweenregenerated catalyst'and hydrogen-rich gas. If desired, however,additional hydrogen-rich or recycle gas may be introduced at 50 inorderto eifect further pretreatment of the catalyst prior to recyclingor discharging the sarne` into. reactor vessel 10 through standpipetransfer line 51. a

The gaseous products from the pretreatmennprincipally the Water vaporformed by the reduction of the catalytic event that it is desired tocompletely exclude the pretreating vapors from the reactor vessel.

In the arrangement as described above it may be seen that the presentinvention permits the intermixing of a stream of recycle reactorcatalyst at essentially reactor temperature with a stream of hot,freshly regenerated catalyst in order to effectively reduce thetemperature of v the regenerated catalyst to a suiciently low point topermit pretreatment of the regenerated catalyst without danger ofovertreatment and/ or thermal degradation while still permitting thecatalyst particles to transfer heat from the regenerator to the reactorside. In addition the present invention prevents water-vapor formed inthe pretreatment of the regenerated catalyst from coming into contactwith the main dense bed in the reactor zone.

The feed or charging stock to the hydroforming reactor may be a virginnaphtha, a cracked naphtha, a Fischer- Tropsch naphtha or the like. Thefeed stock is preheated alone or in admixture with recycle gas toreaction temperature or to the maximum temperature possible whileavoiding thermal degration of the feed stock. Ordinarily preheating ofthe feed stock is carried out to temperatures of about 800-l050 F.,preferably about l 000 F. The naphtha preheat should be as high aspossible while avoiding thermal degredation thereof as by limitingy thetime of residence in the transfer or feed inlet lines. The preheatedfeed stock may be supplied to the reaction vessel in admixture withhydrogen-rich recycle gas or it may be introduced separately as shown.The recycle gas, which contains from about 50 to 80 vol. per centhydrogen is preheated to temperatures of about l1501300 F., preferablyabout 1200 F. prior to the introduction thereof into inlet line 11. Themajor proportion (atleast 85%) of the recycle gas is introduced directlyinto the bottom of reactor vessel 10 while a minor proportion only (atmost about 15%) is introduced into the reactor catalyst recycle line orinto the riser line 48. The recycle gas should be circulated through thereactor at a rate of from about 1000 to 8000, preferably about 4000 cu.ft. per bbl. of naphtha feed. The amount of recycle gas should ingeneral be the minimum amount that will suice to introduce the necessaryportion of the heat of reaction and maintain the amount of carbon formedat a low level.

The reactor system is charged with a mass of finely divided hydroformingcatalyst particles. Suitable catalysts include Group VI metal oxides,such as molybdenum oxide, chromium oxide or tungsten oxide or mixturesthereof upon a carrier such as activated alumina, zinc aluminate spinelor the like. Preferred catalysts contain about to l5 wt. molybdenumoxide or from about to 40 wt. chromium oxide upon a suitable carrier. Ifdesired minor amounts of stabilizers and promoters such as silica,calcium oxide, ceria or potassia can be included in the catalyst. Thecatalyst particles are, for the most part between 200 and V100 mesh insize or about 0-200 microns in diameter with a major proportion between20 and 80 microns.

The hydroforming reactor vessel should be operated at temperaturesbetween about 850 F. and 950 F., preferably about 900 F. and atpressures between 50 and 500 lbs. per sq. inch, preferably about 200lbs. per sq. inch. Temperatures above 900 F. result in increased carbonformation and lower selectivity to gasoline fractions While attemperatures below about 900 F. operating severity is low and wouldtherefore require an excessively large reactiony vessel. Loweringreactor pressure below 200 lbs. per sq. inch generallyresults inincreased carbon formation which in most cases becomes excessive belowabout 'lbs. sq. `Aboven2l00 lbs., however',`'ir

more. The residence time of the regenerator catalyst in contact w1thhydrogen-containing gas prior to reintroduction into the reactor mayvary from about 2-3 seconds to 15 minutes or more. The amount of recyclereactor catalyst added to the stream of regenerated catalyst shouldsuice to y1eld a m1xture of catalyst having a temperature below about1050 F.

The weight ratio of catalyst to oil introduced into the reactor shouldbe about 0.5 to 1.5. operate at catalyst to oil ratios of about 1 sinceratios above about 1 to 1.5 result in excessive carbon formation.

Somewhat higher Weightv ratios can be used at higherA`v Space velocityabout 1.5 Wt./hr./wt. to about 0.15 wt./hr./Wt. The superficial velocityof the gaseous and/ or vaporous materials through the reactor andregenerator is ordinarily between about 0.2 and 0.9 ft. per second.

EXAMPLE 1 In order to determine'the eiect of temperature on the rate andextent of reduction of molybdena, experiments were carried out atatmospheric pressure in which a molybdena-alumina catalyst and pureMoOawere contacted'with"y a stream of pure hydrogen at varioustemperatures for extended periods of time.

l Regenerated at 1,200 F. toconvert all molybdenum to M003 prior toreduction. l v

These experiments show that the M003 on the alumina.

base is less easily reduced than the pure M003 (unsupported). At normalreaction temperatures for hydroforming (about 900 R), it requires anexceedingly long time to reduce the molybdenum on the catalystsignicantly below an equivalent oxidation state of M0205. Attemperatures up to almost 1100 F., the pure unsupported molybdenum canbe easily reduced in Hz below M0205 but not below M002. At the vhightemperatures of 1l00l200 F. desirable in a commercial fluid hydroforming operation from the standpoint of simplicity of equipment,and,l hence, of economics, the molybdenum can be readily reduced belowM002 and leven to metallic molybdenum. This :is representative ofover-pretreatment,

and poor catalyst activity results.

The results of over-pretreatment in relation to catalyst activity andselectivity may be seen from the following experiments carried out on acontinuous 50 B./D. fluid.,

hydroforming pilot plant with a 10% M003 on alumina k'atalyst andfeeding' a 200350 F. virgin Louisiana g It is preferred to of the'weight in pounds of feed chargedperhour per pound of -catalyst in thereactor depends upon the age or activity level of the catalyst, thecharacter of the feed stock and the desired octane number of theproduct. Space-velocity for a molybdenum oxide on alumina gel .catalystmay vary, for example, from The data are summarized naphtha at 900 F 200p. s. i. g., 0.2 w./hr./w., 1 C/Q, 4000 CF/B, with complete regenerationof the catalyst.

l The valence state is dciined as follows: M002; valence ci 6p; M0105;valence of 5.0; MoOz=valence of 4.0, Thus, an averagc'yalence stat-aci4.5 could be made up of equal parts of M001 and M0205. IERwover, 'thevlilatg vilell Stai-G @.1099 99.5 Polt. Si?? filly .exi Ufilntl aboutthe types of oxides present or an average valence state of 4.5 could borepresented equally -Well by l part of M; and 3 par-ts of M002.

`I t is. apparent from the .above experiments that the more reducedstates resulted in poorer eata1yst activity and selectivity, and this isprobably due to some of the molybdene being reduced, under the more.severe reducing oopditions.. to the very low oxides, or .even metallicmolybdeudor, which have little or no catalytic activity. For maximumcatalyst activity, en average valence state Close toil.) is desirable,and this can readily be controlled by carry-ing .out the pretreatmentet. low temperatures.

EXAMBLE z Additional experiments were carried out in a batchuid cyclichydroforrning pilot unit feeding a 200-350 F. virgin Louisiana naphthaover 10% M003 on alumina catalyst at 200 p. s. i. g., 900 F., 0.3W./hr./w., 3000 CEJB. ses. rate, 4for 4.h ou.r hydroforining periods.The time and temperature of prohosting the Catalyst beforeeeehhydroiorrning period were varied and the following results wereobtained i Here again it is shown that both the activity and selectivityof the catalyst are impaired by pretreating at high temperatures fortimes of the orderof one Initiate or more, and the longer the time athigh temperatures, the poorer the results? Qn the. other hund.,extending the time of pretreeting 4et low temperatures to as mush es 15minutes has no appreciable sheet on the eetelyst.

Thus, it is seen 'from the above-described erpermeute that carrying outCatalyst pretreatment .at low temperatures insures optimum catalystactivity and selectivity. and eliminatos the necessity for critical anddifficult. control over the of pretreatment.

EXAMPLE 3,

The adverse effect on the hydrofornging catalyst of the water formedduring pretreatment may lje shown by the following date which wereobtained by continuously pessine controlled amounts of H20 into ebatch-fluid reeetor with the inlet H2 during a hydroforming period. Theequivalerlt amount of water produced 'pretreatment in two-vesselcontinuous lluidhydroforming is given as a function 0f the C/Q ratio.'In the pretreatment of molybdena-containingy catalysts, the reductionnormally proceeds from a Mo valenceof 6 to 5, thus l mol of H20 ferevery two mols of- MoQa reduced,

Operating conditions [200:3 50 F: virgin naphtlhd, molybdena on aluminacatalyst 900 F.. 200 p. s. 1. g.,"0.3 wJhn/w., i-hr, cycle length 3,000C. Fi of inlet H3 Der bbl. oi Feed] 1. OLO ratio required to produce thesalue amount oi Water 0i pretreatmeut es Wes ertitlolelly added .to thereactor in these experiments- It is .apparent that. es the Water contententering the reactor increases the selectivity and activity oi. thehydroiorinins ope 'ou decrease rapidly. Obviously. as. .the C/ Q ratioin .duid hydroiorniing increases, more Water of pretreatment is .Carriedinto the reactor and poorer.A hydroforrning results are obtained-Signifteent improvements een be puede in hydrotorrnine. therefore, bynot permittingthe water iorrned in the pretreatmentto enter the reactorThe foregoing description Contains .a limited number of embodiments ofthe Present invention.- It will be understood, however, thatY numerousvariations are possible without departing .from the seppe of thefollowing claims.

What. is claimed is:

l. In a process for hydroforrning hydrocarbons in con.- tact with finelydivided hydroforrning Catalyst particles comprising molybdenum oxideupon. en alumina-containing support irll accordano@ With the fluidizedsolids technique .at temperatures between about. 850 F- and 950 Fl, atpressures of between about 50 and 500 lbs. per sq. inoh end. .etcatalyst .to oil weight ratios of about 0.5 to

' 11.5., the improvement which comprises Continuously withdrawing astream ot catalyst particles from a reaction Zone., regenerating thewithdrawn catalyst particles by burning e'erbonpeeous depositstherefrom. et elevated ternperptur'es in. e separate regeneration Zone,withdrawing a second or recycle strearri'of catalyst from the reactionzone, withdrawing a stream of regenerated catalyst particles from theregeneration zone, mixing the stream of regenerated catalyst particlessubstantially at regenerator temperature with the second stream ofreactor catalyst substantially at reactor temperature, treating thefreshly regenerated catalyst in admixture with the recycle reactorcatalyst'witli a hydrogen-rich gas in order to reduce the molybdicorrido on the regenerated catalyst particles to a lower, morecatalyticallyv active form of molybdenum orrido, disengaging thecatalyst particles from the hydrogen-rich pretrcatirig lgas and vaporsformed in the hydrof gen treatment of the regenerated catalyst,discharging the gases from the pretrcating operation into the productvapors withdrawn from theV reaction zone and discharging the hydrogentreated catalyst mixture substantially free of pretreating gas andgaseous byproducts of the pre.- treatment step into the reactor densebed thereby avoid,- ing contact of the water vapor formed as aby-product in the pretreatment step with the dense bed of catalyst inthe reaction zone.

2. In a process for hydroforming hydrocarbons in contact with finelydivided hydroforming catalyst particles comprising molybdenum oxide uponan alumina-containing support in accordance with the fluidized solidsteilhnique at temperatures between about 850 F. and 950 at pressures ofbetween about 50 and 500 lbs. per s q. inch and at catalyst to oilweight ratios of about 0,5 to 1.5, the improvement which comprisescontinuously With.- ldrawing astre'am of catalyst particles from areaction zone, stripping entrained end adsorbed hydrogen endhydrocarbons from the withdrawn catalyst,l regenerating the strippedcatalyst particles by burning oerboneeeous h at elevated temperatures ine seperate one, withdrawirig r'a second or recycle maar stream ofcatalyst from the reaction zone, withdrawing a stream of regeneratedcatalyst particles from the regenerstantially at reactor temperature,treating the freshly regenerated catalyst in admixture with the recyclereactor catalyst with a hydrogen-rich gas in order to reduce themolybdic oxide on the regenerated catalyst particles to a lower, morecatalytically active form of molybdenum oxide, disengaging the catalystparticles from the hydrogen-rich pretreating gas and vapors formed inthe vhydrogen treatment of the regenerated catalyst, discharging thegases from the pretreating operation into the product vapors withdrawnfrom the reaction zone and discharging the hydrogen treated catalystmixture substantially free of pretreating gas and gaseous by-products ofthe pretreatment step into the reactor dense bed thereby avoidingcontact of the water vapor formed as a byproduct in the pretreatmentstep with the dense bed of catalyst in the reaction zone. l

3. In a process for hydroforming hydrocarbons in contact with nelydivided hydroforming catalyst particles comprising molybdenum oxide uponau alumina-containing support in accordance with the uidized solidstechnique at temperatures between about 850 F. and 950 F., at pressuresof between about 50 and 500 lbs. per sq. inch and at catalyst to oilweight ratios of about 0.5 to 1.5, the improvement which comprisescontinuously withdrawing a stream of catalyst particles from a reactionzone, regenerating the withdrawn catalyst particles by burningcarbonaceous deposits therefrom at elevated temperatures in a separateregeneration zone, withdrawing a second or recycle stream of catalystfrom the reaction zone at temperatures of about 850-950 F., withdrawinga stream of regenerated catalyst particles from the regeneration zone attemperatures of about l050-1300 F., mixing the stream of regeneratedcatalyst particles with the second stream of reactor catalyst, treatingthe freshly regenerated catalyst in admixture with the recycle reactorcatalyst with a hydrogen-rich gas in order to reduce the molybdic oxideon the regenerated catalyst particles to a lower, more catalyticallyactive form of molybdenum oxide disengaging the catalyst particles fromthe hydrogen-rich pretreating gas and vapors formed in the hydrogentreatment of the regenerated catalyst, discharging the gases from thepretreating operation into the product vapors withdrawn from thereaction zone and discharging the hydrogen treated catalyst mixturesubstantially free of pretreating gas and gaseous by-products of thepretreatment step into the reactor dense bed thereby avoiding contact ofthe water vapor formed as a by-product in the pretreatment step with thedense bed of catalyst in the reaction zone.

4. In a process for hydroforming hydrocarbons in contact with finelydivided hydroforming catalyst particles comprising molybdenum oxide uponan alumina-containing support in accordance with the iluidized solidstechnique at temperatures between about 850 F. and 950 F., at pressuresof between about 50 and 500 lbs. per sq. inch and at catalyst to oilweight rations of about 0.5 to 1.5, the improvement which comprisescontinuously withdrawing a stream of catalyst particles from a reactionzone, stripping entrained and adsorbed hydrogen and hydrocarbons fromthe withdrawn catalyst, regenerating the stripped catalyst particles byburning carbonaceous deposits therefrom at elevated temperatures in aseparate regeneration zone, withdrawing a second or recycle stream ofcatalyst from the reaction zone at temperatures of about 850-950 F.,withdrawing a stream of regenerated catalyst particles from theregeneration zone at temperatures of about 1050-1300 F., strippingcarbon oxides and oxygen from the regenerated catalyst particles, mixingthe stripped regenerated catalyst particles with the second stream ofreactor catalyst, treating the freshly regenerated catalyst in admixturewith the recycle reactor catalyst with a hydrogen-rich gas in order toreduce the molybdic oxide on the regenerated catalyst particles to alower, more catalytically active form of molybdenum oxide, disengagingthe catalyst particles from the hydrogen-rich pretreating gas and vaporsformed inthe hydrogen treatment of the regenerated catalyst, dischargingthegases from the pretreating operation into the product vaporswithdrawn from the reaction zone and discharging the hydrogen treated,catalyst mixture substantially free of pretreating gas andv gaseousby-products of the pretreatment step into the reactor dense bed therebyavoiding contact of the water vapor formed as a by-product in thepretreatment step with the dense bed of catalyst in the reaction zone.

5 In a process for hydroforming hydrocarbons in contact with finelydivided hydroforming catalyst particles comprising molybdenum oxide uponan alumina-containing support in accordance with the uidized solidstechnique at temperatures between about 850 F. and 950 F., at pressuresof between about 50 and 500 lbs. per sq. inch and at catalyst to oilweight ratios of about 0.5 to 1.5, the improvement which comprisescontinuously withdrawing a stream of catalyst particles from a reactionzone, regenerating the withdrawn catalyst particles, by

burning carbonaceous deposits therefrom at elevated teml peratures in aseparate regeneration zone, withdrawing a "second or recycle stream ofcatalyst from the reaction l'zone at temperatures of about 850-9 50 F.,withdrawring a stream of regenerated catalyst particles from theregeneration zone at temperatures of about 1050-1300 F., mixing thestream of regenerated catalyst particles with the second stream ofreactor catalyst, treating the freshly regenerated catalyst in admixturewith the recycle reactor catalyst at temperatures below about 1050 F.with a hydrogen-rich gas in order to reduce the molybdic oxide on theregenerated catalyst particles to a lower,

vmore catalytically active form of molybdenum oxide,

disengaging the catalyst particles from the hydrogen-rich pretreatinggas and vapors formed in the hydrogen treatment of the regeneratedcatalyst, discharging the gases fromthe pretreating operation into theproduct vapors withdrawn from the reaction zone and discharging thehydrogen treated catalyst mixture substantially free of pretreating gasand gaseous by-products of the pretreatment step into the reactor densebed thereby avoiding contact of the water vapor formed as a by-productin the pretreatment step with the dense bed of catalyst in the reactionzone.

6. In a process for hydroforming hydrocarbons in contact with nelydivided hydroforming catalyst particles comprising molybdenum oxide uponan alumina-containing support in accordance with the iluidized solidstechnique at temperatures between about 850 F. and 950 F., at pressuresof between about 50 and 50() lbs. per sq. inch and at catalyst to oilweight ratios of about 0.5 to 1.5, the improvement which comprisescontinuously withdrawing a stream of catalyst particles from a reactionzone, stripping entrained and adsorbed hydrogen and hydrocarbons fromthe withdrawn catalyst, regenerating the stripped catalyst particles byburning carbonaceous deposits therefrom at elevated temperatures in aseparate regeneration zone, withdrawing a second or recycle stream ofcatalyst from the reaction zone at temperatures of about 850-950 F.,withdrawing a stream of regenerated catalyst particles from theregeneration zone at temperatures of about 1050-1300 F., strippingcarbon oxides and oxygen from the regenerated catalyst particles, mixingthe stripped regenerated catalyst particles with the second stream ofreactor catalyst, treating the freshly regenerated catalyst in admixturewith the recycle reactor catalyst at temperatures below about 1050 F.with a hydrogen-rich gas in order` to reduce the molybdic oxide on theregenerated catalyst particles to a lower, more catalytically activeform of molybdenum oxide disengaging einem;

the catalyst particles from the hydrogen-.rich pretreating gas andvapors formed in the hydrogen treatment of the regenerated catalystxdischarging the gases from the Pretreating operation into the productvapors Withdrawn from. the reaction zone and discharging the hydrogentreated catalyst mixture substantially free of pretreating gas andgaseous ley-products ot the pretreatment step into the reactor dense bedthereby avoiding contact ot the water vapor formed as a lay-product inthe pretreatment step with the dense bed of catalyst in the reactionzone.

7. In a process Vfor hydroforming hydrocarbons in contact with nelydivided h ydroforming catalyst particles comprising molybdenum oxideupon au alumina-containing support in accordance with the uidized solidstechnique at temperatures between about 850 F. and 950 F., at pressuresof between about 50 and 500 lbs. per sq. inch and at catalyst to oilweight ratios of about 0.5 to 1.5, the improvement which comprisescontinuously withdrawing a'strearn of catalyst particles from a reactionzone, regenerating the withdrawn catalyst particles by burningcarbonaceous deposits therefrom at elevated temperatures in a separateregeneration zone, withdrawing a second or recycle stream of catalystfrom the reaction zone at temperatures of about 850 F.-950 F.,withdrawing a stream of regenerated catalyst particles from theregeneration zone at temperatures of about 1050"* 1300 F., mixing thestream of regenerated catalyst particles with the second stream ofreactor catalyst, treating the freshly regenerated catalyst in admixturewith the recycle reactor catalyst at temperatures below about 1050 F.with a hydrogen-rich gas for a period of from about 2 seconds to about15 minutes in order to reduce the molybdic oxide on the regeneratedcatalyst particles to a lower, more catalytically active form ofmolybdenum oxide, disengaging the catalyst particles from thehydrogen-rich pretreating gas and vapors formed in the hydrogentreatment of the regenerated catalyst, discharging the gases from thepretreating operation into the product vapors withdrawn from thereaction zone and discharging the hydrogen treated catalyst mixture`substantially free of pretreating gas and `gaseous by-products of thepretreatment step into the reactor dense bed thereby avoiding contact ofthe water vapor `orrned as a lay-product in the pretreatment step withthe dense bed of catalyst in the reaction zone.

8. In a process for hydroforming hydrocarbons in con- 12 tactwith-finely divided hydroforrning catalyst particles comprisingmolybdenum oxide upon an alumina-containing support in accordance withthe fluidized solids technique 4at. temperatures between about 850 F.and 950 F., 'at pressuresv of about 50 and 500 lbs. per sq inch and atcatalyst t9 Oil weight ratios of about 0.5 to 1.5, the improvement whichcomprises continuously withdrawing a stream of catalyst particles from areaction Zone, strip- Ping entrained and adsorbed hydrogen andhydrocarbons from the withdrawn catalyst, regenerating the strippedcatalyst particles by burning carbollaceous deposits therefrom atelevated temperatures in a separate regeneration zone, withdrawing asecond or recycle stream of catalyst from the reaction zone attemperatures of about 850- 950" F., withdrawing a stream of regeneratedcatalyst particles from the regeneration ,zone at temperatures of about10501300 F., stripping carbon oxides and oxygen from the regeneratedcatalyst particles, mixing the stripped regenerated catalyst particleswith the second stream of reactor catalyst, treating the freshlyregenerated catalyst in adrnixture' with the recycle reactor catalyst attemperatures below about 1050 F. with a hydrogen-rich gas for a periodof from about 2 seconds to about l5 minutes in order to reduce themolybdic oxide on the regenerated catalyst particles to a lower, morecatalytically' active form of molybdenum oxide, disengaging the catalystparticles from the hydrogen-rich pretreating gas and vapors formed inthe hydrogen treatment of the regenerated catalyst, discharging thegases from the pretreating operation into the product vapors withdrawnfrom the reaction zone and discharging the hydrogen treated catalystmixture substantially free of pretreating gas and gaseous by-products ofthe pretreatment step into the reactor dense bed thereby avoidingcontact of the water vapor formed as a lay-product in the pretreatmentstep with the dense bed of catalyst in the reaction zone.

References Cited in the le of this patent UNITED STATES PATENTS2,345,487 Liedholm Mar. 28, 1944 2,410,891 Meinert et al. Nov. 12, 19462,459,824. Letter Ian. 25, 1949 2,472,844 Munday et al June 14, 19492,490,993 Boroherding Dec. 13, 1949 2,700,639 Weikart Jan. 25, 1955

1. IN A PROCESS FOR HYDROFORMING HYDROCARBONS IN CONTACT WITH FINELYDIVIDED HYDROFORMING CATALYST PARTICLES COMPRISING MOLYHBDRNUM OXIDEUPON AN ALUMINA-CONTAINING SUPPORT IN ACCORDANCE WITH THE FLUIDIZEDSOLIDS TECHNIQUE AT TEMPERATURES BETWEEN ABOUT 850* F. AND 950* F., ATPRESSURES OF BETWEEN ABOUT 50 AND 500 LBS. PER SQ. INCH AND AT CATALYSTTO OIL WEIGHT RATIOS OF ABOUT 0.5 TO 1.5, THE IMPROVEMENT WHICHCOMPRISES CONTINUOUSLY WITHDRAWING A STREAM OF CATALYST PARTICLES FROM AREACTION ZONE, REGENERATING THE WITHDRAWN CATALYST PARTICLES BY BURNINGCARBONACEOUS DEPOSITS THEREFROM AT ELEVATED TEMPERATURES IN A SEPARATEREGENERATION ZONE, WITHDRAWING A SECOND OR RECYCLE STREAM OF CATALYSTFROM THE REACTION ZONE, WITHDRAWING A STREAM OF REGENERATED CATALYSTPARTICLES FROM THE REGENERATION ZONE, MIXING THE STREAM OF REGENERATEDCATALYST PARTICLES SUBSTANTIALLY AT REGENERATOR TEMPERATURE WITH THESECOND STREAM OF REACTOR CATALYST SUBSTANTIALLY AT REACTOR TEMPERATURE,TREATING THE FRESHLY REGENERATED CATALYST IN ADMIXTURE WITH THE RECYCLEREACTOR CATALYST WITH A HYDROGEN-RICH GAS IN ORDER TO REDUCE THEMOLYBDIC OXIDE ON THE REGENERATED CATALYST PARTICLES TO A LOWER, MORECATALYTICALLY ACTIVE FORM OF MOLYBDENUM OXIDE, DISENGAGING THE CATALYSTPARTICLES FROM THE HYDROGEN-RICH PRETREATING GAS AND VAPORS FORMED INTHE HYDROGEN TREATMENT OF THE REGENERATED CATALYST, DISCHARGING THEGASES FROM THE PRETREATING OPERATION INTO THE PRODUCT VAPORS WITHDRAWNFROM THE REACTION ZONE AND DISCHARGING THE HYDROGEN TREATED CATALYSTMIXTURE SUBSTANTIALLY FREE OF PRETREATING GAS AND GASEOUS BY-PRODUCTS OFTHE PRETREATMENT STEP INTO THE REACTOR DENSE BED THEREBY AVOIDINGCONTACT OF THE WATER VAPOR FORMED AS A BY-PRODUCT IN THE PRETREATMENTSTEP WITH THE DENSE BED OF CATALYST IN THE REACTION ZONE.